Like everyone else has alreay said - do not put it in checked baggage. I've never had a problem with up to 400 speed film (fastest I usually carry), even after a few runs thru the x-ray. What I have done is to put all my film into a separate bag (non-xray type, maybe a ziploc even) and run that thru the machine after my camera bag. They'll stop the belt to really check out my camera bag (all those cords and batteries probably look suspicious) but the film won't be in there when they do it. The film just sails right through unharmed.